Chart Dates: Part 1 of 3

An update to allow users to define a specific date
range for a chart on the home window. This update
only applies to the LTM chart and only allows a
date range from/to to be defined.

It would be nice to also support a last 'n' 'period'
selection too (i.e. last n days/weeks/months).

Also, further updates are required to add similar
functionality to TreeMap, CP, Dist and Summary charts
when they are on the home window.